There are two general categories of mammographic findings suggestive of a breast cancer: soft tissue masses and suspicious microcalcifications.

Soft tissue mass/architectural distortion 

— The most specific mammographic feature of malignancy is a spiculated soft tissue mass; nearly 90 percent of these lesions represent invasive cancer.

Mammogram spiculated mass

Image

Spot magnification view of a mammogram showing two small adjacent interconnected spiculated masses (red arrows). Pathology revealed tubular carcinoma. Tubular carcinoma characteristically appears spiculated on mammogram and is often associated with satellite lesions.

Courtesy of Lisa E Esserman, MD.

 

Microcalcifications 

— Grouped microcalcifications are calcium particles of various size and shape measuring between 0.1 to 1 mm in diameter and numbering more than four to five per cubic centimeter. Microcalcifications are seen in approximately 60 percent of cancers detected mammographically (image 3A-B). Histologically, these represent intraductal calcifications in areas of necrotic tumor (picture 1) or calcifications within mucin-secreting tumors such as the cribriform or micropapillary subtype of intraductal cancer. (See "Pathology of breast cancer".)

Linear branching microcalcifications (image 3A-B), most commonly associated with the comedo histologic subtype, have a higher predictive value for malignancy than do coarse heterogeneous (ie, nonlinear irregular calcifications of varying size and shape) microcalcifications, particularly for high-grade ductal carcinoma in situ (DCIS). However, breast cancers, including DCIS, more often present with the granular type of calcifications [11]. Calcifications that are not suspicious for malignancy and considered benign include vascular and skin calcifications, rim calcifications, large and coarse calcifications (image 4), and smooth round or oval calcifications (image 5).

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Mammographic findings such as masses and calcifications can be stratified by suspicion for malignancy, and the BI-RADS 4a, 4b, and 4c categories are helpful in alerting the referring physicians, the pathologists, and surgeons to the underlying risk of malignancy [15,20]. Grouped coarse heterogeneous calcifications have a likelihood of malignancy of just under 15 percent, while amorphous calcifications have a likelihood of malignancy of 20 percent. Both would be assessed as BI-RADS 4b (table 1) [21]. Grouped round and punctate calcifications at baseline have a probability of malignancy of less than 2 percent and can be safely placed in a short-interval (six-month) follow-up category as BI-RADS 3: Probably Benign. (See 'BI-RADS assessment categories' above.)

Assessing the extent of disease — Mammographic assessment of the extent of DCIS and early invasive carcinoma begins during diagnostic mammography and continues through the biopsy, specimen management, and the postexcision mammogram [11]. Mammography of both breasts is particularly important in the patient with DCIS or invasive cancer who is considering breast conservation. Preoperative diagnostic mammography can help to define the extent of disease and may identify multifocal or multicentric cancer that could preclude breast conservation or signal a potential difficulty in achieving clear surgical margins. Multifocal disease is usually defined as involvement of several areas within a breast quadrant, probably representing disease along an entire duct. In contrast, multicentric disease involves multiple areas within different quadrants, probably representing involvement of multiple ducts.

Although the extent of mammographic nonlinear branching microcalcifications frequently underestimates the pathologic extent of the malignancy, the discrepancy is less than 2 cm in 80 to 85 percent of cases [22]. Several groups of microcalcifications separated by normal-appearing tissue should not be interpreted as multifocal or multicentric disease. Often, these represent areas of contiguous tumor that is only partially calcified within a ductal-lobule [22,23]. As well, multiple groups of calcifications that are separated by normal breast tissue should be confirmed to be malignant before using the information as a basis for what to resect if it would change the surgical approach.

The combination of a mass and associated calcifications often indicates the presence of an extensive intraductal component (EIC). EIC is defined pathologically as DCIS found adjacent to an invasive carcinoma, accounting for more than 25 percent of the volume of disease. This finding can be a predictor for more widespread residual tumor (usually DCIS) following gross excision of the lesion [24]. (See "Breast ductal carcinoma in situ: Epidemiology, clinical manifestations, and diagnosis".)

Postoperative mammograms to look for residual calcifications after surgical resection should be performed when the microcalcifications are not clearly or completely documented on the specimen radiograph or when margins are close or positive [25-27]. If a re-excision is to be recommended on the basis of residual calcifications, care should be taken to ensure that the calcifications are associated with malignancy on histopathology and not benign tissue. Multifocal disease is not necessarily a contraindication to breast conservation but is one of the factors that should be taken into consideration along with breast size relative to the extent of disease on imaging. (See "Breast conserving therapy" and "Breast ductal carcinoma in situ: Epidemiology, clinical manifestations, and diagnosis".)

A significant limitation of mammographic assessment of disease extent is the obscuring of the borders or extent of the primary tumor by dense overlying tissue. Dense breasts can limit the sensitivity of mammography both for detection of breast cancers and for delineating disease extent [28,29]. In this setting, contrast-enhanced breast magnetic resonance imaging (MRI) may complement mammographic staging. If the clinical extent of disease is larger than what can be appreciated by mammography, MRI may be considered. (See 'Breast MRI' below.)

Mammographic assessment of tumor size for the staging of multifocal disease presents a unique dilemma. Most staging classifications require that the largest tumor mass be utilized for T staging, even in cases where multifocal disease is suspected. However, others suggest that the total surface area, volume, or aggregate measurements are a better indicator of prognosis [30-32]. Accurate delineation of the extent of odd-shaped, irregular, or multifocal tumors is important for treatment planning. (See "Tumor, Node, Metastasis (TNM) staging classification for breast cancer".)

For invasive cancers that are contiguous to the chest wall and not completely included on mammographic projections, ancillary imaging techniques such as MRI may be necessary to assess posterior tumor extension and pectoralis fascia or muscle involvement if that will determine a change in surgical approach or the use of neoadjuvant therapy [33]. (See 'Assessment of ipsilateral disease with breast MRI' below.)

Significance of intramammary lymph nodes — Intramammary lymph nodes are detected in 1 to 28 percent of patients with breast cancer [34-38]. Benign nodes can often be distinguished from metastatic or infiltrated intramammary lymph nodes by their mammographic or sonographic appearance, but definitive assessment often requires histopathologic study [39]. The presence of intramammary lymph node metastases appears to confer a worse prognosis, both in women who otherwise have stage I breast cancer based upon tumor size and axillary nodal status and in those with stage II disease [34]. Isolated intramammary lymph node metastases are considered to represent stage II disease, even if the axillary nodes are uninvolved. (See "Tumor, Node, Metastasis (TNM) staging classification for breast cancer".)

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An abnormal mammogram shows findings suspicious for malignancy. These are white areas on film or digital screen representing high-density tissue with irregular edges.

A mammogram is also abnornal when

(1) a small cluster of calcifications shows around a whitish area on the x-ray film.

(2) An isolated cluster of tiny, irregular calcifications, especially if linear and wispy.

(3) Skin thickening is also an important prognostic indicator.

(4) Whitish areas with ill-defined borders.

 

With spiculated borders, or an architectural distortion, or an asymmetric increased tissue density when compared with prior studies or a corresponding area in the opposite breast.

 

Mammogram showing spiculated mass. Early intraductal carcinoma of the right breast. Craniocaudal (A) and oblique mediolateral (B) views of the right breast show a spiculated mass in the upper outer quadrant.

 

With these mammographic findings, it is important to obtain tissue for histologic diagnosis. Because of the high risk of malignancy, a stereotactic-directed core biopsy, or surgical excisional biopsy, is preferable to a fine needle aspiration.

For needle localization, mammographic guidance is employed so that the end of the needle is placed in the center of the suspicious area. The surgeon may then perform a breast biopsy using the needle as a guide. Because the mass is not palpable, a needle-localized approach is needed. Needle-localization biopsies employ multiple mammographic views of the breast and allow the surgeon to localize the lesion for evaluation. It is more time consuming, carries a comparable 3% to 5% miss rate, but excises more tissue, which is helpful in "borderline" histologic conditions, such as ductal carcinoma-in-situ.

The other option is a stereotactic core biopsy. The patient is prone on the mammographic table and biopsies are taken as directed with computer-assisted imaging techniques. This method employs a computerized, digital, three-dimensional view of the breast and allows the physician to direct the needle to the biopsy site. The procedure carries a 2% to 4% "miss rate."

1. Breast cancer

2. Fat necrosis:Trauma to the breast may lead to fat necrosis and produce mammographic findings similar to that seen in breast cancer. These lesions should be excised to confirm the diagnosis.

 

 

References

American College of Obstetricians and Gynecologists. Breast cancer screening. ACOG Practice Bulletin 42. April 2003.

Hacker NF, Friedlander ML. Breast disease: a gynecologic perspective. In: Hacker NF, Gambone JC, Hobel CJ, eds. Essentials of Obstetrics and Gynecology, 5th ed. Philadelphia, PA: Saunders; 2009:332-344.

Valea FA, Katz VL. Breast diseases. In: Katz VL, Lentz GM, Lobo RA, Gersenson DM, eds. Comprehensive Gynecology. 5th ed. St. Louis, MP: Mosby-Year Book; 2007:327-357.

 

Pivotal Assessment Finding

Vacuum Assisted Biopsy

(VAB)

Papilloma
Breast Carcinioma

https://www.breastsurgeons.org/about/statements/PDF_Statements/Concordance_and_High%20RiskLesions.pdf

 


A 40-year-old woman undergoes a screening mammogram which reveals a lesion of the right breast, showing an ill-defined mass with a cluster of calcifications. She recalls bumping her right breast against a door knob leading to a bruise approximately 1 year previously. Which of the following is the most likely diagnosis?

A. Ductal carcinoma-in-situ
B. Infiltrating intraductal carcinoma
C. Fat necrosis
D. Lobular carcinoma

Correct Answer: C.

Explanation: Fat necrosis resulting from trauma to the breast often leads to mammographic findings that are identical to breast cancer. This patient recalls trauma to the breast in the location of the mammographic abnormality. To further evaluate the patient and confirm the diagnosis, a biopsy should be performed. Cancer is still a concern, and infiltrating intraductal carcinoma is the most common histological subtype.

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QUESTION 2:

A 39-year-old woman physicist is referred by her physician for a screening mammogram. She asks about the amount of radiation exposure, and the cumulative risk of cancers due to the radiation. Which of the following describes the radiation risk with modern mammography given once annually?

A. Increased risk for thyroid cancer
B. No increased risks
C. Increased risk for lung cancer
D. Increased risk of skin cancer in the chest area

Correct Answer: B.

Explanation: Modern mammography has very low radiation and no increased risk of cancer.


QUESTION 3:

A 55-year-old woman has several coarse calcifications found on mammography that are suspicious for breast cancer. She has no family history of breast cancer and no mass is palpable. Which of the following is the most accurate statement?

A. The best diagnostic method for this patient is fine-needle aspiration.
B. The next best step is MRI of the lesion.
C. Since there is no palpable mass on physical examination, the patient may be observed for changes on mammography in 3 months.
D. One option for this patient is a core tissue biopsy by stereotactic means.

Correct Answer: D.

Explanation: Mammographic findings that are suspicious for cancer must be addressed. Two viable methods include core biopsy via stereotactic guidance and needle-localization excision. Fine-needle aspiration is not sensitive enough, and no mass is palpable to be able to serve for localizing. MRI does not add to an already suspicious lesion.



 

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